Sorry, but there is nothing related to MAC Addresses in the RTC SDK.
What I did find out about MAC Addresses after googling for a bit, is that an IP packet no longer contains a MAC Address of its origin after the packet has passed a few locations (routers, gateways, firewalls or proxies) and the only way for a Server to find out the MAC Address of the Client would be to send the Client a packet and ask for it.
Here is a Forum discussion about obtaining MAC Addresses from remote clients (Linux?):
http://www.linuxquestions.org/questions/programming-9/remote-client-mac-address-on-socket-descriptor-850092Here is an article with an example in VC++ for Windows (looks promissing):
http://www.binarytides.com/get-mac-address-from-ip-in-winsock/And here is a Forum Thread with an example in Delphi:
http://www.borlandtalk.com/indy-how-to-obtain-peers-mac-adress--vt43051.htmlI hope that helps. If not, try using Google. There are a lot of articles and Forum threads about this subject.
Best Regards,
Danijel Tkalcec